The Voice Coil Positioning Stage is a compact, small footprint positioning stage. It is ideal for closed loop positioning applications with a short stroke where intricate position, velocity, and acceleration control is necessary.

Their compact size allows them to fit into small spaces. They have very low electrical and mechanical time constants. The low moving mass allows for high accelerations of light payloads.

The ironless core coil assembly has no magnetic attractive force to the stationary magnet assembly, which reduces the load on the bearing system, which increases the life of the bearing. There are no magnetic drag forces (hysteresis), which allows for higher accelerations.

These actuators are wound in such a way that no commutation is required for motion to occur. Electrical devices such as Hall Effects are not necessary. The result is a much simpler and more reliable system.

Bearings: Linear guidance and stiffness is achieved by using high precision ball slides or cross roller slides. Other types of bearings and bushings are available depending on the application.

Feedback: Non-contact optical or magnetic linear encoders with a center reference mark for homing. Typical encoder output is A and B square wave signals but sinusoidal output is available as an option. Analog feedback is available via LVDT or Force Transducer.

Limit Switches: Soft limits are typically used and monitored by the controller. But, if needed, end of travel limit switches may be included at both ends of the stroke. The switches can be either active high/low (5V to 24V). The limit switches can be used to shut down the amplifier or to signal the controller that an error has occurred. The limit switches can be an integral part of the encoder or can be mounted separately if required.

Hard Stops: Hard stops are incorporated into the ends of the stage to prevent over travel damage in the event of servo system failure.

Advantages:

Small Size, High Force to Weight Ratio

High Accelerations

No Cogging or Commutation

Custom Designs with Quick Turnaround Times

High Flux Density Neodymium Magnets are Used

Low Cost Economical Solution

Applications:

Mirror Tilt and Focusing

Z Axis for Pick and Place Equipment

Medical Diagnostic Probes and Laser Beam Steering

Vision Inspection

Miniature Position Control

Clean room

Stages can be ordered for any stroke up to 2 inches and any continuous force up to 100 lbs. The stages are built as the orders are placed, they are not stocked, as each customer requirement is different.

It should be noted that for both types of actuators (NCC & NCM) used for these stages, longer strokes are available but the efficiency or motor constant (Km) decreases as the stroke increases. This is due to the fact that the motor constant is inversely proportional to the stroke. If higher efficiency is desired for longer stroke actuators, the coil assembly can be wound as a multiphase coil and then it will have to be commutated. Please consult the factory for long stroke applications.

H2W Technologies, Inc. is dedicated to the design and manufacture of linear and rotary motion products that are used in the motion control industry. The complete line of linear electric motors includes: Single and dual axis linear steppers, DC brush and brushless linear motors, voice coil actuators, and AC induction motors. Also offered is a complete line of ball screw, lead screw and belt driven positioning stages.